A plague on both your houses - Susanna Gregory

A Plague on Both your Houses
Meet physician Matthew Bartholomew, whose unorthodox but effective treatment of his patients frequently draws accusations of heresy from his more traditional colleagues.
Besides his practice, Bartholomew is teacher of Medicine at Michaelhouse, part of the fledgling University of Cambridge.
In 1348, the inhabitants of Cambridge live under the shadow of a terrible pestilence that has ravaged Europe and is travelling relentlessly eastward towards England.
Bartholomew, however, is distracted by the sudden and inexplicable death of the Master of Michaelhouse - a death the University authorities do not want investigated.
When three more scholars die in mysterious circumstances, Bartholomew defies the University and begins his own enquiry.
And then the Black Death finally arrives...

An Unholy Alliance
Two years after the Black Death hit England, the people of Cambridge are still struggling to overcome its effects.
Bands of outlaws roam the land and the high death rate among priests and monks has left the people vulnerable to sinister cults that have grown up in the wake of the plague.
At Michaelhouse, Matthew Bartholomew is training new physicians to replace those who died of the pestilence when the body of a friar is found in the University's massive document chest.
Then Bartholomew is shocked to discover the meeting place for a mysterious sect which holds its followers in terror, and which could be at the very heart of an astonishing web of blackmail and deceit aimed to overthrow the established religion.